The ultimate aim of this study of ocular pressure-regulating mechanisms is to improve the treatment of glaucoma. This study includes the following approaches to the problem; investigation of the inflow and outflow of aqueous humor in the eyes of patients and experimental animals, examination of the functional and physical character of the outflow channels of enucleated human and animal eyes, and determination of the influence of physiologic, pharmacologic and pathologic factors on aqueous formation, flow and pressure. Techniques employed for these studies include tonography, gonioscopy, angiography, perfusion, microdissection, histologic, bioassay, and chemical methods. Some of the techniques have been specially devised for the purpose by the Principal Investigator and co-workers. New methods of treatment which may be evolved in these studies will be tested in experimental animals, and if sufficiently promising, on patients. The clinical portions of this research includes detailed studies of patients with glaucoma to establish better the characteristics, causes and natural course of the different kinds of glaucoma, to evaluate the influence of physiologic variables within the patient, and to examine the effects of surgical and medical treatments both for beneficial action and for the possibility of undesirable side effects.